# renderToMarkup

> This method should only be used on the server.

Renders all cached styles grouped CSS strings and returns a valid HTML markup with `<style>` elements. The elements are grouped and sorted in the following order:

1. Fonts
2. Static Styles
3. Keyframes
4. Rules
5. Support Rules
6. Media Query Rules
7. Support & Media Query Rules

The DOM renderer is able to rehydrate its cache from the markup in order to skip initial rendering.

## Arguments

| Argument | Type                            | Description                                                                      |
| -------- | ------------------------------- | -------------------------------------------------------------------------------- |
| renderer | [_Renderer_](api/fela/renderer) | The renderer providing the styles which are rendered to stringified HTML markup. |

## Returns

(_string_): Single concatenated HTML markup string containing required `<style>` elements.

## Example

```js
import { renderToMarkup } from 'fela-dom'
import { createRenderer } from 'fela'

const renderer = createRenderer()

const rule = ({ fontSize }) => ({
  fontSize: fontSize,
  color: 'blue',
  '@supports (display: flex)': {
    color: 'green',
  },
  '@media (min-width: 300px)': {
    color: 'red',
  },
})

renderer.renderStatic('html,body{box-sizing:border-box;margin:0}')
renderer.renderRule(rule, { fontSize: '12px' })

const markup = renderToMarkup(renderer)
```

The following markup would be returned:

```html
<style type="text/css" data-fela-type="STATIC" data-fela-rehydration="4">
  html,
  body {
    box-sizing: border-box;
    margin: 0;
  }
</style>
<style type="text/css" data-fela-type="RULE" data-fela-rehydration="4">
  .a {
    font-size: 12px;
  }
  .b {
    color: blue;
  }
</style>
<style
  type="text/css"
  data-fela-type="RULE"
  data-fela-rehydration="4"
  data-fela-support
>
  .c {
    color: green;
  }
</style>
<style
  type="text/css"
  data-fela-type="RULE"
  data-fela-rehydration="4"
  media="(min-width: 300px)"
>
  .d {
    color: red;
  }
</style>
```
